Thermal and spectroscopic studies of scandium complex of 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone

The scandium complexes of Sc(PMBP)₃·H₂O (non-crystal) and Sc(PMBP)₃ (crystal) with 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP) were prepared and characterized by thermal analysis, IR, NMR and MS spectroscopies. The crystal structure of the complex, obtained by X-ray analysis, indicates that PMBP is a bidentate ligand in the complex and that the Sc atom is six-coordinate and is in a meridional octahedral environment. The order of the ring current effect on the pyrazolone ring is Sc(PMBP)₃ >PMBP(enol)> PMBP(keto).

The metal to ligand stoichiometry was found to be 1:3. The crystalline complex melts at 209 °C, followed by degradation at about 310 °C, with the beginning of decomposition. The enthalpy of melting was found to be 61 kJ/mol. On the other hand, the non-crystalline complex was found to change into a crystalline complex at 176 °C with an exothermic reaction before melting at 217 °C. The IR band observed at approximately, 450 cm⁻¹ is possibly due to the stretching of the Sc–O bond.     

Recovery of plutonium from oxalate supernatant using 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone

Summary Extraction of Pu(IV) from oxalate supernatant was carried out employing 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP) in xylene as extractant. The conditions for quantitative extraction were determined by the variation of ligand, oxalic acid and nitric acid concentration. Quantitative stripping was achieved using a mixture of 0.4M oxalic acid and 0.4M ammonium oxalate. Extraction of Pu(IV) from synthetic oxalate supernatant solution containing 3M nitric acid and 0.2M oxalic acid was investigated under various loading conditions employing 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone in xylene as extractant. Under uranium loading conditions the Pu extraction decreased significantly while with increased Pu loading whereas the D_Pu value was influenced marginally. The effect of a redox reagent on Pu extraction was also investigated.     

Tautomerism of 1-phenyl-3-methyl-4-benzyl-5-pyrazolone

The tautomerism of 1-phenyl-3-methyl-4-benzyl-5-pyrazolone —a side product in the reaction of acetoacetic ester with benzaldehyde phenylhydrazone — was studied by IR and PMR spectroscopy, and its thermodynamic characteristics were determined.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 355–359, March, 1991.     

Thermal decomposition of iron(III) complex of 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone

A pyrazolonate (PMBP) of iron(III) was prepared and its metal to ligand stoichiometry was shown to be 1∶3. The decomposition of the complex was studied by thermogravimetry and differential analyses under an air atmosphere. The complex undergos two endothermic reactions without loss in mass, at 160 and 218°C, followed by an exothermic reaction at 480°C involving decomposition of the ligands. Intermediates obtained by melting of the Fe-PMBP complex were characterized by X-ray diffraction analysis. The Fe-PMBP complex was confirmed by HPLC to be a mixture of two isomers.     

Anionic lanthanide complexes with 3-methyl-4-formyl-1-phenyl-5-pyrazolone

The coordination compounds Na[LnL₄] · 2H₂O and [NBu₄][LnL₄] (Ln = Nd, Sm, Eu, Tb; HL is 3-methyl-4-formyl-1-phenyl-5-pyrazolone) have been synthesized and studied by IR spectroscopy and thermogravimetry. According to X-ray diffraction data, the coordination polyhedra of lanthanides are shaped as square antiprisms and formed by the oxygen atoms of four deprotonated moieties of the enol form of 4-formyl-5-pyrazolone. In the complex Na[EuL₄] · 2H₂O, sodium cations are bonded to the two nitrogen atoms of pyrazole heterocycles, combining discrete complex anions into two interpenetrating three-dimensional frameworks. Polycrystalline samples of neodymium(III), samarium(III), and terbium(III) complexes manifest intense luminescence in the spectral regions that are typical for them.     

Mixed ligand chelate extraction of lanthanides with 1-phenyl-3-methyl-4-octanoyl-5-pyrazolone systems

The equilibrium extraction behavior for a series of representative trivalent lanthanide ions, Pr, Eu, and Yb, using chloroform solutions containing 1-phenyl-3-methyl-4-octanoyl-5-pyrazolone (HPMOP), either alone or combined with 1,10-phenanthroline (phen), trioctylphosphine oxide (TOPO) or methyltrioctylaromonium chloride (R₃R'NCl), is studied. The results demonstrate that these lanthanides are extracted as LnP₃, or in the presence of phen or TOPO. as LnP₃ · phen or LnP₃ · TOPO, or in the presence of R₃R'NCl, as R₃R'NLnP₄. The effects of phen, TOPO, and R₃R—NCl on the extraction of lanthanide ions with HPMOP are more pronounced than their effects with 8-quinolinol or 5,7-dibromo-8-quinolinol.     

Studies on extraction of manganese(II) with 1-phenyl-3-methyl-4-acyl-5-pyrazolone

The extraction of Mn(II) with 1-phenyl-3-methyl-4-acyl-5-pyrazolone (HA) in MIBK has been studied. Mn(II) is extracted as MnA(2). The extraction constant for each 4-acyl compound was calculated. The effect of temperature on the extraction of Mn(II) has also been investigated.     

Studies on extraction of copper(II) with 1-phenyl-3-methyl-4-acyl-5-pyrazolone

The extraction of Cu(II) with 1-phenyl-3-methyl-4-acyl-5-pyrazolone (HA), in different organic solvents has been studied. The extraction mechanism of Cu(II) and the composition of the extracted species has been determined. Cu(II) was extracted as CuA₂, or in the presence of TOPO, as CuA₂TOPO. The extraction constants do not change regularly with increasing the length of acyl chain in the 1-phenyl-3-methyl-4-acyl-5-pyrazolone derivatives. The effect of the temperature on the extraction of Cu(II) has also been investigated.     

Adduct formation properties of mono- and bidentate phosphine oxide compounds in the liquid—liquid extraction of some divalent metals with 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone

The bidentate phosphine oxide compounds bis(diphenylphosphinyl)methane (BDPPM) and bis(diphenylphosphinyl)ethane (BDPPE) were synthesized and the liquid—liquid extraction equilibria of some divalent metal ions such as Co(II), Ni(II), Zn(II) and Cd(II) with 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (HPMBP) and the neutral phosphine oxide compounds were investigated. BDPPM was found to be much more powerful than BDPPE and the monodentate neutral ligand trioctylphosphine oxide (TOPO). The composition of the extracted species were determined by a graphical method to be M(PMBP)₂(TOPO)_s (s = 2 for Co, Ni, Cd and s = 1 for Zn), M(PMBP)₂(BDPPM) and M(PMBP)₂(BDPPE). The adduct formation constants between the acylpyrazolone chelates and the neutral ligands were determined and are discussed in terms of the molecular structure.     

Extraction of thorium(IV) by a mixture of 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone and tri-n-octyl phosphine oxide

The extraction behavior of Th(IV) from dilute nitric as well as perchloric acid medium using 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP) and its mixture with tri-n-octyl phosphine oxide (TOPO) was investigated. The species of the type Th(X)(PMBP)₃·(HPMBP) and Th(X)(PMBP)₃·(TOPO) were extracted for the binary and ternary extraction systems, respectively, where X=NO₃− or ClO₄−. The presence of 1.25·10⁻⁵M Th carrier in the aqueous phase resulted in the extracted species of the type of Th(PMBP)₄ and Th(PMBP)₄·(TOPO), respectively. The extraction constant (logk _ex ) for the binary species Th(PMBP)₄ was found to be 6.89±0.01 while the overall extraction constant (logK) for the ternary species Th(PMBP)₄·(TOPO) was calculated to be 13.17±0.06.     

Preconcentration of indium with 1-phenyl-3-methyl-4-stearoyl-5-pyrazolone on silica gel

Indium was quantitatively retained at pH > 2.8, and could be removed by treatment with 1 M hydrochloric acid. The adsorption capacity of the material was 32 μmol In g^?1. Nickel, cobalt and zinc had no effect on the retention of indium.     

The solid-state michael addition of 3-methyl-1-phenyl-5-pyrazolone

A novel solid-state Michael addition between pyrazolone 1 and 4-arylidenepyrazolones 2 at ambient temperature produced Michael adducts, 4,4′-arylidenebis(3-methyl-1-phenyl-5-pyrazolones) 3. Pyrazolones 3 formed salts 4 with Cu²⁺ in solution, indicating the enolic structure of the pyrazolone rings. The reactivity of 2 with 1 is discussed in terms of the electronic and steric effects of the substituent on the arylidene group of compounds 2 . Pyrazolone 1 also underwent the solid state Michael addition reaction with maleimide at 100° to give the adducts 7,8 and 9 .     

Solvent extraction of calcium(II) and strontium(II) with 1-phenyl-3-methyl-4-acyl-5-pyrazolone

The extraction of calcium and strontium from aqueous solution with 1-phenyl-3-methyl-4-acyl-5-pyrazolone (C_n) in MIBK and benzyl alcohol has been studied. In the extraction of Sr with 4-acyl derivatives-MIBK systems, the pH_1/2 values change with increasing the length of acyl chain in the derivatives. The reagent C₃ is more suitable than the other reagents for the separation of Ca and Sr, using MIBK as solvent.     

H2BPMOPP和PMBP协同萃取Ln3+的研究

4-酰代双吡唑啉酮对金属离子具有很强的萃取能力。本文在合成萃取剂1，2-双(1′-苯基-3′-甲基-5′-氧代吡唑-4′-基)邻苯二酮(H2BPMOPP-H2A)的基础上，     

铌(V)-1-苯基-3-甲基-4-苯甲酰基-吡唑啉酮-5络合物吸附波的研究

在pH=5.0的HAc-NaAc介质中,Nb(V)与1-苯基-3-甲基-4-苯甲酰基-吡唑啉酮-5(PMBP)生成络合物,于-0.96V(us.SCE)出现一尖锐的极谱波.在滴汞电极上用示波极谱仪或在悬汞电极上测吸附伏安曲线.峰电流与Nb(V)浓度分别在0.0075~0.80μg/mL及0.000075~0.0075μg/mL范围内呈线性关系.实验了30多种离子的干扰影响,经苯肿酸分离后用于钢中Nb(V)的测定.检出限为0.00003μg/mL.溶液可稳定96h以上.用多种电化学方法研究了电极反应机理.     

Thermal decompositions of complexes of Al,Ga, In,Cr, Fe and Bi ions with 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone

The thermal decompositions of Al, Ga, In, Cr, Fe and Bi complexes with 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone have been studied in a nitrogen atmosphere. The thermal stabilities of these complexes follow the sequence Bi<Fe<Ga<In<Cr<Al. In the cases of Al, Ga and In, a linear relationship was obtained between the melting points of the complexes and the ionic radii of the central metals.     

C-alkylation of 3-methyl-1-phenyl-5-pyrazolone by hexafluoroacetone and its imines

Conclusions Regiospecificity was demonstrated for C-alkylation in the reactions of 3-methyl-1-phenyl-5-pyrazolone with hexafluoroacetone and the trifluoroacetylimine and benzenesulfonylimine of hexafluoroacetone at C⁴ of the heterocycle.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 684–686, March, 1987.     

Crystal structure and photoisomerism of 1-phenyl-3-methyl-4-benzal-5-pyrazolone 4-butylthiosemicarbazone in solid state

The structure of 1-phenyl-3-methyl-4-benzal-5-pyrazolone 4-butylthiosemicarbazone (PMBP-BTSC) was confirmed by¹H NMR, IR, elemental analyses, and X-ray crystallographic analysis. The photoisomerization of PMBP-BTSC in solid state was studied in the condition of UV-Vis irradiation, and the mechanism of the photoisomerization was interpreted by double proton transfer. Moreover, the effect of the alkyl chain length in the side chain of a series of 4-acyl pyrazolone derivatives on the photochemical properties was discussed.